3Bake 8 to 11 minutes or until set (do not overbake). Cool 2 minutes; remove from cookie sheets to cooling racks. Cool completely, about 15 minutes.

4In large bowl, beat filling ingredients with electric mixer on high speed until light and fluffy. For each whoopie pie, spread about 2 tablespoons filling on bottom of 1 cooled cookie. Top with second cookie, bottom side down. Store covered in refrigerator.